From “A History of the Apostolic Church” by Afshin Khorami
When Christianity was introduced to the Arsacid Empire, the Persians already had an ancient and well-established religion; Zoroastrianism. Founded by the Prophet Zoroaster, Zoroastrianism taught that the world existed in a state of struggle between the benevolent creator god Ahura Mazda and the evil spirit Angra Mainyu. Humans, in this worldview, are free to choose between good, or asha, and evil, or druj. Zoroastrianism spread throughout what is today Persia after Zoroaster’s death, eventually becoming the state religion of the Achaemenid Empire. Following the Macedonian conquests, Zoroastrianism lost its status as state religion, with Hellenistic beliefs taking its place. Zoroastrianism would regain state support with the ascendency of the Arsacids, but by this point it had changed significantly. While Zoroastrians originally worshipped in outdoor locations, they now did so in fire temples. While the Avesta[1] had once been purely oral tradition, it was now beginning to be written down. And most significantly, the religion had absorbed numerous foreign deities and concepts. Syncretism between Zoroastrianism and Greek and Mesopotamian religions was encouraged by the Arsacid shahs, who also made an effort to deify themselves.
Despite the absorption of foreign concepts, Zoroastrianism remained strongly tied to the Persian identity. Indeed, most of the early converts to Christianity in the Arsacid Empire were not Persians, but Aramaic-speaking Mesopotamians. That said, Christianity would make inroads in Persia, especially in major urban centers. Most converts were from the urban poor and slaves, while the upper classes and countryside staid true to their ancestral Zoroastrian religion. However, once Christianity arrived in Persia, it was bound to converge with Zoroastrian ideas. At a basic level, the two religions had similar ideas; both believed in a benevolent, omnipotent creator god, both believed that the afterlife saw reward or punishment based on actions in life, and, crucially, they both believed in a savior figure. The idea of Jesus as the Messiah foretold in the Old Testament, sent to redeem mankind and die for their sins forms the basis of Christian belief. The Zoroastrians, meanwhile, told of a coming savior figure known as the Saoshyant. According to the Avesta, the Saoshyant would come at the end of time to bring about the Frashokereti, or the final victory of good against evil.
According Zoroastrian tradition[2], the Saoshyant would be born of a virgin, much like Jesus was. Likewise, many of the details of the Saoshyant’s coming life and accomplishments are similar to Jewish traditions about the Messiah. Furthermore, the magi who visited the baby Jesus were Zoroastrian priests. All of these facts meant that Christian missionaries presented Jesus as having been the Saoshyant foretold in the Avesta. If Jesus had been the Saoshyant, this logically meant that Zoroaster had been a legitimate prophet, and that Ahura Mazda was one and the same as the God of Abraham. Christians presented their religion as not only a realization of Judaism, but also a revival of the original principles of Zoroastrianism which had been practiced under the Achaemenids(praises in the Old Testament and held in high regard by both Christian and non-Christian Persians) but which had been forgotten over time. Christianity would likewise adopt other Zoroastrianism. For example, Nowruz was originally the Zoroastrian new year before it was was claimed as the day when Christ was born. Many of the archangels recognized by the Apostolic Church, meanwhile, were once the Zoroastrian Spenta Mainyu.
Many Christians sought to separate “philosophical Zoroastrianism”, which was seen as Zoroaster’s original teachings which were compatible with Christianity, and “religious Zoroastrianism”, which was a pagan corruption. Zoroaster’s core precepts of “good thoughts, good words, good deeds” were praised by Christian thinkers. Meanwhile, the worship of deities such as Mithra, Anahita, and so forth was condemned as entirely alien to Zoroaster’s teachings. For this reason, the Gathas(hymns written by Zoroaster himself) were and are recognized by the Church as having been divinely inspired, while the rest of the Avesta(which was compiled by the magi over time) is largely ignored in a Christian thought. Nevertheless, the syncretism between Christianity and Zoroastrianism greatly facilitated the spread of Christianity in Persia.
[1]Zoroastrian holy text
[2]Apocryphal tradition, not in the Avesta
